xref: /openbmc/linux/drivers/mmc/host/sdhci-tegra.c (revision d943f6e9)
1 /*
2  * Copyright (C) 2010 Google, Inc.
3  *
4  * This software is licensed under the terms of the GNU General Public
5  * License version 2, as published by the Free Software Foundation, and
6  * may be copied, distributed, and modified under those terms.
7  *
8  * This program is distributed in the hope that it will be useful,
9  * but WITHOUT ANY WARRANTY; without even the implied warranty of
10  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
11  * GNU General Public License for more details.
12  *
13  */
14 
15 #include <linux/delay.h>
16 #include <linux/err.h>
17 #include <linux/module.h>
18 #include <linux/init.h>
19 #include <linux/iopoll.h>
20 #include <linux/platform_device.h>
21 #include <linux/clk.h>
22 #include <linux/io.h>
23 #include <linux/of.h>
24 #include <linux/of_device.h>
25 #include <linux/pinctrl/consumer.h>
26 #include <linux/regulator/consumer.h>
27 #include <linux/reset.h>
28 #include <linux/mmc/card.h>
29 #include <linux/mmc/host.h>
30 #include <linux/mmc/mmc.h>
31 #include <linux/mmc/slot-gpio.h>
32 #include <linux/gpio/consumer.h>
33 
34 #include "sdhci-pltfm.h"
35 
36 /* Tegra SDHOST controller vendor register definitions */
37 #define SDHCI_TEGRA_VENDOR_CLOCK_CTRL			0x100
38 #define SDHCI_CLOCK_CTRL_TAP_MASK			0x00ff0000
39 #define SDHCI_CLOCK_CTRL_TAP_SHIFT			16
40 #define SDHCI_CLOCK_CTRL_SDR50_TUNING_OVERRIDE		BIT(5)
41 #define SDHCI_CLOCK_CTRL_PADPIPE_CLKEN_OVERRIDE		BIT(3)
42 #define SDHCI_CLOCK_CTRL_SPI_MODE_CLKEN_OVERRIDE	BIT(2)
43 
44 #define SDHCI_TEGRA_VENDOR_MISC_CTRL			0x120
45 #define SDHCI_MISC_CTRL_ENABLE_SDR104			0x8
46 #define SDHCI_MISC_CTRL_ENABLE_SDR50			0x10
47 #define SDHCI_MISC_CTRL_ENABLE_SDHCI_SPEC_300		0x20
48 #define SDHCI_MISC_CTRL_ENABLE_DDR50			0x200
49 
50 #define SDHCI_TEGRA_AUTO_CAL_CONFIG			0x1e4
51 #define SDHCI_AUTO_CAL_START				BIT(31)
52 #define SDHCI_AUTO_CAL_ENABLE				BIT(29)
53 #define SDHCI_AUTO_CAL_PDPU_OFFSET_MASK			0x0000ffff
54 
55 #define SDHCI_TEGRA_SDMEM_COMP_PADCTRL			0x1e0
56 #define SDHCI_TEGRA_SDMEM_COMP_PADCTRL_VREF_SEL_MASK	0x0000000f
57 #define SDHCI_TEGRA_SDMEM_COMP_PADCTRL_VREF_SEL_VAL	0x7
58 #define SDHCI_TEGRA_SDMEM_COMP_PADCTRL_E_INPUT_E_PWRD	BIT(31)
59 
60 #define SDHCI_TEGRA_AUTO_CAL_STATUS			0x1ec
61 #define SDHCI_TEGRA_AUTO_CAL_ACTIVE			BIT(31)
62 
63 #define NVQUIRK_FORCE_SDHCI_SPEC_200			BIT(0)
64 #define NVQUIRK_ENABLE_BLOCK_GAP_DET			BIT(1)
65 #define NVQUIRK_ENABLE_SDHCI_SPEC_300			BIT(2)
66 #define NVQUIRK_ENABLE_SDR50				BIT(3)
67 #define NVQUIRK_ENABLE_SDR104				BIT(4)
68 #define NVQUIRK_ENABLE_DDR50				BIT(5)
69 #define NVQUIRK_HAS_PADCALIB				BIT(6)
70 #define NVQUIRK_NEEDS_PAD_CONTROL			BIT(7)
71 
72 struct sdhci_tegra_soc_data {
73 	const struct sdhci_pltfm_data *pdata;
74 	u32 nvquirks;
75 };
76 
77 /* Magic pull up and pull down pad calibration offsets */
78 struct sdhci_tegra_autocal_offsets {
79 	u32 pull_up_3v3;
80 	u32 pull_down_3v3;
81 	u32 pull_up_3v3_timeout;
82 	u32 pull_down_3v3_timeout;
83 	u32 pull_up_1v8;
84 	u32 pull_down_1v8;
85 	u32 pull_up_1v8_timeout;
86 	u32 pull_down_1v8_timeout;
87 	u32 pull_up_sdr104;
88 	u32 pull_down_sdr104;
89 	u32 pull_up_hs400;
90 	u32 pull_down_hs400;
91 };
92 
93 struct sdhci_tegra {
94 	const struct sdhci_tegra_soc_data *soc_data;
95 	struct gpio_desc *power_gpio;
96 	bool ddr_signaling;
97 	bool pad_calib_required;
98 	bool pad_control_available;
99 
100 	struct reset_control *rst;
101 	struct pinctrl *pinctrl_sdmmc;
102 	struct pinctrl_state *pinctrl_state_3v3;
103 	struct pinctrl_state *pinctrl_state_1v8;
104 
105 	struct sdhci_tegra_autocal_offsets autocal_offsets;
106 };
107 
108 static u16 tegra_sdhci_readw(struct sdhci_host *host, int reg)
109 {
110 	struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
111 	struct sdhci_tegra *tegra_host = sdhci_pltfm_priv(pltfm_host);
112 	const struct sdhci_tegra_soc_data *soc_data = tegra_host->soc_data;
113 
114 	if (unlikely((soc_data->nvquirks & NVQUIRK_FORCE_SDHCI_SPEC_200) &&
115 			(reg == SDHCI_HOST_VERSION))) {
116 		/* Erratum: Version register is invalid in HW. */
117 		return SDHCI_SPEC_200;
118 	}
119 
120 	return readw(host->ioaddr + reg);
121 }
122 
123 static void tegra_sdhci_writew(struct sdhci_host *host, u16 val, int reg)
124 {
125 	struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
126 
127 	switch (reg) {
128 	case SDHCI_TRANSFER_MODE:
129 		/*
130 		 * Postpone this write, we must do it together with a
131 		 * command write that is down below.
132 		 */
133 		pltfm_host->xfer_mode_shadow = val;
134 		return;
135 	case SDHCI_COMMAND:
136 		writel((val << 16) | pltfm_host->xfer_mode_shadow,
137 			host->ioaddr + SDHCI_TRANSFER_MODE);
138 		return;
139 	}
140 
141 	writew(val, host->ioaddr + reg);
142 }
143 
144 static void tegra_sdhci_writel(struct sdhci_host *host, u32 val, int reg)
145 {
146 	struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
147 	struct sdhci_tegra *tegra_host = sdhci_pltfm_priv(pltfm_host);
148 	const struct sdhci_tegra_soc_data *soc_data = tegra_host->soc_data;
149 
150 	/* Seems like we're getting spurious timeout and crc errors, so
151 	 * disable signalling of them. In case of real errors software
152 	 * timers should take care of eventually detecting them.
153 	 */
154 	if (unlikely(reg == SDHCI_SIGNAL_ENABLE))
155 		val &= ~(SDHCI_INT_TIMEOUT|SDHCI_INT_CRC);
156 
157 	writel(val, host->ioaddr + reg);
158 
159 	if (unlikely((soc_data->nvquirks & NVQUIRK_ENABLE_BLOCK_GAP_DET) &&
160 			(reg == SDHCI_INT_ENABLE))) {
161 		/* Erratum: Must enable block gap interrupt detection */
162 		u8 gap_ctrl = readb(host->ioaddr + SDHCI_BLOCK_GAP_CONTROL);
163 		if (val & SDHCI_INT_CARD_INT)
164 			gap_ctrl |= 0x8;
165 		else
166 			gap_ctrl &= ~0x8;
167 		writeb(gap_ctrl, host->ioaddr + SDHCI_BLOCK_GAP_CONTROL);
168 	}
169 }
170 
171 static unsigned int tegra_sdhci_get_ro(struct sdhci_host *host)
172 {
173 	return mmc_gpio_get_ro(host->mmc);
174 }
175 
176 static bool tegra_sdhci_is_pad_and_regulator_valid(struct sdhci_host *host)
177 {
178 	struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
179 	struct sdhci_tegra *tegra_host = sdhci_pltfm_priv(pltfm_host);
180 	int has_1v8, has_3v3;
181 
182 	/*
183 	 * The SoCs which have NVQUIRK_NEEDS_PAD_CONTROL require software pad
184 	 * voltage configuration in order to perform voltage switching. This
185 	 * means that valid pinctrl info is required on SDHCI instances capable
186 	 * of performing voltage switching. Whether or not an SDHCI instance is
187 	 * capable of voltage switching is determined based on the regulator.
188 	 */
189 
190 	if (!(tegra_host->soc_data->nvquirks & NVQUIRK_NEEDS_PAD_CONTROL))
191 		return true;
192 
193 	if (IS_ERR(host->mmc->supply.vqmmc))
194 		return false;
195 
196 	has_1v8 = regulator_is_supported_voltage(host->mmc->supply.vqmmc,
197 						 1700000, 1950000);
198 
199 	has_3v3 = regulator_is_supported_voltage(host->mmc->supply.vqmmc,
200 						 2700000, 3600000);
201 
202 	if (has_1v8 == 1 && has_3v3 == 1)
203 		return tegra_host->pad_control_available;
204 
205 	/* Fixed voltage, no pad control required. */
206 	return true;
207 }
208 
209 static void tegra_sdhci_reset(struct sdhci_host *host, u8 mask)
210 {
211 	struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
212 	struct sdhci_tegra *tegra_host = sdhci_pltfm_priv(pltfm_host);
213 	const struct sdhci_tegra_soc_data *soc_data = tegra_host->soc_data;
214 	u32 misc_ctrl, clk_ctrl, pad_ctrl;
215 
216 	sdhci_reset(host, mask);
217 
218 	if (!(mask & SDHCI_RESET_ALL))
219 		return;
220 
221 	misc_ctrl = sdhci_readl(host, SDHCI_TEGRA_VENDOR_MISC_CTRL);
222 	clk_ctrl = sdhci_readl(host, SDHCI_TEGRA_VENDOR_CLOCK_CTRL);
223 
224 	misc_ctrl &= ~(SDHCI_MISC_CTRL_ENABLE_SDHCI_SPEC_300 |
225 		       SDHCI_MISC_CTRL_ENABLE_SDR50 |
226 		       SDHCI_MISC_CTRL_ENABLE_DDR50 |
227 		       SDHCI_MISC_CTRL_ENABLE_SDR104);
228 
229 	clk_ctrl &= ~SDHCI_CLOCK_CTRL_SPI_MODE_CLKEN_OVERRIDE;
230 
231 	if (tegra_sdhci_is_pad_and_regulator_valid(host)) {
232 		/* Erratum: Enable SDHCI spec v3.00 support */
233 		if (soc_data->nvquirks & NVQUIRK_ENABLE_SDHCI_SPEC_300)
234 			misc_ctrl |= SDHCI_MISC_CTRL_ENABLE_SDHCI_SPEC_300;
235 		/* Advertise UHS modes as supported by host */
236 		if (soc_data->nvquirks & NVQUIRK_ENABLE_SDR50)
237 			misc_ctrl |= SDHCI_MISC_CTRL_ENABLE_SDR50;
238 		if (soc_data->nvquirks & NVQUIRK_ENABLE_DDR50)
239 			misc_ctrl |= SDHCI_MISC_CTRL_ENABLE_DDR50;
240 		if (soc_data->nvquirks & NVQUIRK_ENABLE_SDR104)
241 			misc_ctrl |= SDHCI_MISC_CTRL_ENABLE_SDR104;
242 		if (soc_data->nvquirks & SDHCI_MISC_CTRL_ENABLE_SDR50)
243 			clk_ctrl |= SDHCI_CLOCK_CTRL_SDR50_TUNING_OVERRIDE;
244 	}
245 
246 	sdhci_writel(host, misc_ctrl, SDHCI_TEGRA_VENDOR_MISC_CTRL);
247 	sdhci_writel(host, clk_ctrl, SDHCI_TEGRA_VENDOR_CLOCK_CTRL);
248 
249 	if (soc_data->nvquirks & NVQUIRK_HAS_PADCALIB) {
250 		pad_ctrl = sdhci_readl(host, SDHCI_TEGRA_SDMEM_COMP_PADCTRL);
251 		pad_ctrl &= ~SDHCI_TEGRA_SDMEM_COMP_PADCTRL_VREF_SEL_MASK;
252 		pad_ctrl |= SDHCI_TEGRA_SDMEM_COMP_PADCTRL_VREF_SEL_VAL;
253 		sdhci_writel(host, pad_ctrl, SDHCI_TEGRA_SDMEM_COMP_PADCTRL);
254 
255 		tegra_host->pad_calib_required = true;
256 	}
257 
258 	tegra_host->ddr_signaling = false;
259 }
260 
261 static void tegra_sdhci_configure_cal_pad(struct sdhci_host *host, bool enable)
262 {
263 	u32 val;
264 
265 	/*
266 	 * Enable or disable the additional I/O pad used by the drive strength
267 	 * calibration process.
268 	 */
269 	val = sdhci_readl(host, SDHCI_TEGRA_SDMEM_COMP_PADCTRL);
270 
271 	if (enable)
272 		val |= SDHCI_TEGRA_SDMEM_COMP_PADCTRL_E_INPUT_E_PWRD;
273 	else
274 		val &= ~SDHCI_TEGRA_SDMEM_COMP_PADCTRL_E_INPUT_E_PWRD;
275 
276 	sdhci_writel(host, val, SDHCI_TEGRA_SDMEM_COMP_PADCTRL);
277 
278 	if (enable)
279 		usleep_range(1, 2);
280 }
281 
282 static bool tegra_sdhci_configure_card_clk(struct sdhci_host *host, bool enable)
283 {
284 	bool status;
285 	u32 reg;
286 
287 	reg = sdhci_readw(host, SDHCI_CLOCK_CONTROL);
288 	status = !!(reg & SDHCI_CLOCK_CARD_EN);
289 
290 	if (status == enable)
291 		return status;
292 
293 	if (enable)
294 		reg |= SDHCI_CLOCK_CARD_EN;
295 	else
296 		reg &= ~SDHCI_CLOCK_CARD_EN;
297 
298 	sdhci_writew(host, reg, SDHCI_CLOCK_CONTROL);
299 
300 	return status;
301 }
302 
303 static void tegra_sdhci_set_pad_autocal_offset(struct sdhci_host *host,
304 					       u16 pdpu)
305 {
306 	u32 reg;
307 
308 	reg = sdhci_readl(host, SDHCI_TEGRA_AUTO_CAL_CONFIG);
309 	reg &= ~SDHCI_AUTO_CAL_PDPU_OFFSET_MASK;
310 	reg |= pdpu;
311 	sdhci_writel(host, reg, SDHCI_TEGRA_AUTO_CAL_CONFIG);
312 }
313 
314 static void tegra_sdhci_pad_autocalib(struct sdhci_host *host)
315 {
316 	struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
317 	struct sdhci_tegra *tegra_host = sdhci_pltfm_priv(pltfm_host);
318 	struct sdhci_tegra_autocal_offsets offsets =
319 			tegra_host->autocal_offsets;
320 	struct mmc_ios *ios = &host->mmc->ios;
321 	bool card_clk_enabled;
322 	u16 pdpu;
323 	u32 reg;
324 	int ret;
325 
326 	switch (ios->timing) {
327 	case MMC_TIMING_UHS_SDR104:
328 		pdpu = offsets.pull_down_sdr104 << 8 | offsets.pull_up_sdr104;
329 		break;
330 	case MMC_TIMING_MMC_HS400:
331 		pdpu = offsets.pull_down_hs400 << 8 | offsets.pull_up_hs400;
332 		break;
333 	default:
334 		if (ios->signal_voltage == MMC_SIGNAL_VOLTAGE_180)
335 			pdpu = offsets.pull_down_1v8 << 8 | offsets.pull_up_1v8;
336 		else
337 			pdpu = offsets.pull_down_3v3 << 8 | offsets.pull_up_3v3;
338 	}
339 
340 	tegra_sdhci_set_pad_autocal_offset(host, pdpu);
341 
342 	card_clk_enabled = tegra_sdhci_configure_card_clk(host, false);
343 
344 	tegra_sdhci_configure_cal_pad(host, true);
345 
346 	reg = sdhci_readl(host, SDHCI_TEGRA_AUTO_CAL_CONFIG);
347 	reg |= SDHCI_AUTO_CAL_ENABLE | SDHCI_AUTO_CAL_START;
348 	sdhci_writel(host, reg, SDHCI_TEGRA_AUTO_CAL_CONFIG);
349 
350 	usleep_range(1, 2);
351 	/* 10 ms timeout */
352 	ret = readl_poll_timeout(host->ioaddr + SDHCI_TEGRA_AUTO_CAL_STATUS,
353 				 reg, !(reg & SDHCI_TEGRA_AUTO_CAL_ACTIVE),
354 				 1000, 10000);
355 
356 	tegra_sdhci_configure_cal_pad(host, false);
357 
358 	tegra_sdhci_configure_card_clk(host, card_clk_enabled);
359 
360 	if (ret) {
361 		dev_err(mmc_dev(host->mmc), "Pad autocal timed out\n");
362 
363 		if (ios->signal_voltage == MMC_SIGNAL_VOLTAGE_180)
364 			pdpu = offsets.pull_down_1v8_timeout << 8 |
365 			       offsets.pull_up_1v8_timeout;
366 		else
367 			pdpu = offsets.pull_down_3v3_timeout << 8 |
368 			       offsets.pull_up_3v3_timeout;
369 
370 		/* Disable automatic calibration and use fixed offsets */
371 		reg = sdhci_readl(host, SDHCI_TEGRA_AUTO_CAL_CONFIG);
372 		reg &= ~SDHCI_AUTO_CAL_ENABLE;
373 		sdhci_writel(host, reg, SDHCI_TEGRA_AUTO_CAL_CONFIG);
374 
375 		tegra_sdhci_set_pad_autocal_offset(host, pdpu);
376 	}
377 }
378 
379 static void tegra_sdhci_parse_pad_autocal_dt(struct sdhci_host *host)
380 {
381 	struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
382 	struct sdhci_tegra *tegra_host = sdhci_pltfm_priv(pltfm_host);
383 	struct sdhci_tegra_autocal_offsets *autocal =
384 			&tegra_host->autocal_offsets;
385 	int err;
386 
387 	err = device_property_read_u32(host->mmc->parent,
388 			"nvidia,pad-autocal-pull-up-offset-3v3",
389 			&autocal->pull_up_3v3);
390 	if (err)
391 		autocal->pull_up_3v3 = 0;
392 
393 	err = device_property_read_u32(host->mmc->parent,
394 			"nvidia,pad-autocal-pull-down-offset-3v3",
395 			&autocal->pull_down_3v3);
396 	if (err)
397 		autocal->pull_down_3v3 = 0;
398 
399 	err = device_property_read_u32(host->mmc->parent,
400 			"nvidia,pad-autocal-pull-up-offset-1v8",
401 			&autocal->pull_up_1v8);
402 	if (err)
403 		autocal->pull_up_1v8 = 0;
404 
405 	err = device_property_read_u32(host->mmc->parent,
406 			"nvidia,pad-autocal-pull-down-offset-1v8",
407 			&autocal->pull_down_1v8);
408 	if (err)
409 		autocal->pull_down_1v8 = 0;
410 
411 	err = device_property_read_u32(host->mmc->parent,
412 			"nvidia,pad-autocal-pull-up-offset-3v3-timeout",
413 			&autocal->pull_up_3v3);
414 	if (err)
415 		autocal->pull_up_3v3_timeout = 0;
416 
417 	err = device_property_read_u32(host->mmc->parent,
418 			"nvidia,pad-autocal-pull-down-offset-3v3-timeout",
419 			&autocal->pull_down_3v3);
420 	if (err)
421 		autocal->pull_down_3v3_timeout = 0;
422 
423 	err = device_property_read_u32(host->mmc->parent,
424 			"nvidia,pad-autocal-pull-up-offset-1v8-timeout",
425 			&autocal->pull_up_1v8);
426 	if (err)
427 		autocal->pull_up_1v8_timeout = 0;
428 
429 	err = device_property_read_u32(host->mmc->parent,
430 			"nvidia,pad-autocal-pull-down-offset-1v8-timeout",
431 			&autocal->pull_down_1v8);
432 	if (err)
433 		autocal->pull_down_1v8_timeout = 0;
434 
435 	err = device_property_read_u32(host->mmc->parent,
436 			"nvidia,pad-autocal-pull-up-offset-sdr104",
437 			&autocal->pull_up_sdr104);
438 	if (err)
439 		autocal->pull_up_sdr104 = autocal->pull_up_1v8;
440 
441 	err = device_property_read_u32(host->mmc->parent,
442 			"nvidia,pad-autocal-pull-down-offset-sdr104",
443 			&autocal->pull_down_sdr104);
444 	if (err)
445 		autocal->pull_down_sdr104 = autocal->pull_down_1v8;
446 
447 	err = device_property_read_u32(host->mmc->parent,
448 			"nvidia,pad-autocal-pull-up-offset-hs400",
449 			&autocal->pull_up_hs400);
450 	if (err)
451 		autocal->pull_up_hs400 = autocal->pull_up_1v8;
452 
453 	err = device_property_read_u32(host->mmc->parent,
454 			"nvidia,pad-autocal-pull-down-offset-hs400",
455 			&autocal->pull_down_hs400);
456 	if (err)
457 		autocal->pull_down_hs400 = autocal->pull_down_1v8;
458 }
459 
460 static void tegra_sdhci_set_clock(struct sdhci_host *host, unsigned int clock)
461 {
462 	struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
463 	struct sdhci_tegra *tegra_host = sdhci_pltfm_priv(pltfm_host);
464 	unsigned long host_clk;
465 
466 	if (!clock)
467 		return sdhci_set_clock(host, clock);
468 
469 	/*
470 	 * In DDR50/52 modes the Tegra SDHCI controllers require the SDHCI
471 	 * divider to be configured to divided the host clock by two. The SDHCI
472 	 * clock divider is calculated as part of sdhci_set_clock() by
473 	 * sdhci_calc_clk(). The divider is calculated from host->max_clk and
474 	 * the requested clock rate.
475 	 *
476 	 * By setting the host->max_clk to clock * 2 the divider calculation
477 	 * will always result in the correct value for DDR50/52 modes,
478 	 * regardless of clock rate rounding, which may happen if the value
479 	 * from clk_get_rate() is used.
480 	 */
481 	host_clk = tegra_host->ddr_signaling ? clock * 2 : clock;
482 	clk_set_rate(pltfm_host->clk, host_clk);
483 	if (tegra_host->ddr_signaling)
484 		host->max_clk = host_clk;
485 	else
486 		host->max_clk = clk_get_rate(pltfm_host->clk);
487 
488 	sdhci_set_clock(host, clock);
489 
490 	if (tegra_host->pad_calib_required) {
491 		tegra_sdhci_pad_autocalib(host);
492 		tegra_host->pad_calib_required = false;
493 	}
494 }
495 
496 static void tegra_sdhci_set_uhs_signaling(struct sdhci_host *host,
497 					  unsigned timing)
498 {
499 	struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
500 	struct sdhci_tegra *tegra_host = sdhci_pltfm_priv(pltfm_host);
501 
502 	if (timing == MMC_TIMING_UHS_DDR50 ||
503 	    timing == MMC_TIMING_MMC_DDR52)
504 		tegra_host->ddr_signaling = true;
505 
506 	sdhci_set_uhs_signaling(host, timing);
507 }
508 
509 static unsigned int tegra_sdhci_get_max_clock(struct sdhci_host *host)
510 {
511 	struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
512 
513 	return clk_round_rate(pltfm_host->clk, UINT_MAX);
514 }
515 
516 static void tegra_sdhci_set_tap(struct sdhci_host *host, unsigned int tap)
517 {
518 	u32 reg;
519 
520 	reg = sdhci_readl(host, SDHCI_TEGRA_VENDOR_CLOCK_CTRL);
521 	reg &= ~SDHCI_CLOCK_CTRL_TAP_MASK;
522 	reg |= tap << SDHCI_CLOCK_CTRL_TAP_SHIFT;
523 	sdhci_writel(host, reg, SDHCI_TEGRA_VENDOR_CLOCK_CTRL);
524 }
525 
526 static int tegra_sdhci_execute_tuning(struct sdhci_host *host, u32 opcode)
527 {
528 	unsigned int min, max;
529 
530 	/*
531 	 * Start search for minimum tap value at 10, as smaller values are
532 	 * may wrongly be reported as working but fail at higher speeds,
533 	 * according to the TRM.
534 	 */
535 	min = 10;
536 	while (min < 255) {
537 		tegra_sdhci_set_tap(host, min);
538 		if (!mmc_send_tuning(host->mmc, opcode, NULL))
539 			break;
540 		min++;
541 	}
542 
543 	/* Find the maximum tap value that still passes. */
544 	max = min + 1;
545 	while (max < 255) {
546 		tegra_sdhci_set_tap(host, max);
547 		if (mmc_send_tuning(host->mmc, opcode, NULL)) {
548 			max--;
549 			break;
550 		}
551 		max++;
552 	}
553 
554 	/* The TRM states the ideal tap value is at 75% in the passing range. */
555 	tegra_sdhci_set_tap(host, min + ((max - min) * 3 / 4));
556 
557 	return mmc_send_tuning(host->mmc, opcode, NULL);
558 }
559 
560 static int tegra_sdhci_set_padctrl(struct sdhci_host *host, int voltage)
561 {
562 	struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
563 	struct sdhci_tegra *tegra_host = sdhci_pltfm_priv(pltfm_host);
564 	int ret;
565 
566 	if (!tegra_host->pad_control_available)
567 		return 0;
568 
569 	if (voltage == MMC_SIGNAL_VOLTAGE_180) {
570 		ret = pinctrl_select_state(tegra_host->pinctrl_sdmmc,
571 					   tegra_host->pinctrl_state_1v8);
572 		if (ret < 0)
573 			dev_err(mmc_dev(host->mmc),
574 				"setting 1.8V failed, ret: %d\n", ret);
575 	} else {
576 		ret = pinctrl_select_state(tegra_host->pinctrl_sdmmc,
577 					   tegra_host->pinctrl_state_3v3);
578 		if (ret < 0)
579 			dev_err(mmc_dev(host->mmc),
580 				"setting 3.3V failed, ret: %d\n", ret);
581 	}
582 
583 	return ret;
584 }
585 
586 static int sdhci_tegra_start_signal_voltage_switch(struct mmc_host *mmc,
587 						   struct mmc_ios *ios)
588 {
589 	struct sdhci_host *host = mmc_priv(mmc);
590 	struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
591 	struct sdhci_tegra *tegra_host = sdhci_pltfm_priv(pltfm_host);
592 	int ret = 0;
593 
594 	if (ios->signal_voltage == MMC_SIGNAL_VOLTAGE_330) {
595 		ret = tegra_sdhci_set_padctrl(host, ios->signal_voltage);
596 		if (ret < 0)
597 			return ret;
598 		ret = sdhci_start_signal_voltage_switch(mmc, ios);
599 	} else if (ios->signal_voltage == MMC_SIGNAL_VOLTAGE_180) {
600 		ret = sdhci_start_signal_voltage_switch(mmc, ios);
601 		if (ret < 0)
602 			return ret;
603 		ret = tegra_sdhci_set_padctrl(host, ios->signal_voltage);
604 	}
605 
606 	if (tegra_host->pad_calib_required)
607 		tegra_sdhci_pad_autocalib(host);
608 
609 	return ret;
610 }
611 
612 static int tegra_sdhci_init_pinctrl_info(struct device *dev,
613 					 struct sdhci_tegra *tegra_host)
614 {
615 	tegra_host->pinctrl_sdmmc = devm_pinctrl_get(dev);
616 	if (IS_ERR(tegra_host->pinctrl_sdmmc)) {
617 		dev_dbg(dev, "No pinctrl info, err: %ld\n",
618 			PTR_ERR(tegra_host->pinctrl_sdmmc));
619 		return -1;
620 	}
621 
622 	tegra_host->pinctrl_state_3v3 =
623 		pinctrl_lookup_state(tegra_host->pinctrl_sdmmc, "sdmmc-3v3");
624 	if (IS_ERR(tegra_host->pinctrl_state_3v3)) {
625 		dev_warn(dev, "Missing 3.3V pad state, err: %ld\n",
626 			 PTR_ERR(tegra_host->pinctrl_state_3v3));
627 		return -1;
628 	}
629 
630 	tegra_host->pinctrl_state_1v8 =
631 		pinctrl_lookup_state(tegra_host->pinctrl_sdmmc, "sdmmc-1v8");
632 	if (IS_ERR(tegra_host->pinctrl_state_1v8)) {
633 		dev_warn(dev, "Missing 1.8V pad state, err: %ld\n",
634 			 PTR_ERR(tegra_host->pinctrl_state_3v3));
635 		return -1;
636 	}
637 
638 	tegra_host->pad_control_available = true;
639 
640 	return 0;
641 }
642 
643 static void tegra_sdhci_voltage_switch(struct sdhci_host *host)
644 {
645 	struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
646 	struct sdhci_tegra *tegra_host = sdhci_pltfm_priv(pltfm_host);
647 	const struct sdhci_tegra_soc_data *soc_data = tegra_host->soc_data;
648 
649 	if (soc_data->nvquirks & NVQUIRK_HAS_PADCALIB)
650 		tegra_host->pad_calib_required = true;
651 }
652 
653 static const struct sdhci_ops tegra_sdhci_ops = {
654 	.get_ro     = tegra_sdhci_get_ro,
655 	.read_w     = tegra_sdhci_readw,
656 	.write_l    = tegra_sdhci_writel,
657 	.set_clock  = tegra_sdhci_set_clock,
658 	.set_bus_width = sdhci_set_bus_width,
659 	.reset      = tegra_sdhci_reset,
660 	.platform_execute_tuning = tegra_sdhci_execute_tuning,
661 	.set_uhs_signaling = tegra_sdhci_set_uhs_signaling,
662 	.voltage_switch = tegra_sdhci_voltage_switch,
663 	.get_max_clock = tegra_sdhci_get_max_clock,
664 };
665 
666 static const struct sdhci_pltfm_data sdhci_tegra20_pdata = {
667 	.quirks = SDHCI_QUIRK_BROKEN_TIMEOUT_VAL |
668 		  SDHCI_QUIRK_SINGLE_POWER_WRITE |
669 		  SDHCI_QUIRK_NO_HISPD_BIT |
670 		  SDHCI_QUIRK_BROKEN_ADMA_ZEROLEN_DESC |
671 		  SDHCI_QUIRK_CAP_CLOCK_BASE_BROKEN,
672 	.ops  = &tegra_sdhci_ops,
673 };
674 
675 static const struct sdhci_tegra_soc_data soc_data_tegra20 = {
676 	.pdata = &sdhci_tegra20_pdata,
677 	.nvquirks = NVQUIRK_FORCE_SDHCI_SPEC_200 |
678 		    NVQUIRK_ENABLE_BLOCK_GAP_DET,
679 };
680 
681 static const struct sdhci_pltfm_data sdhci_tegra30_pdata = {
682 	.quirks = SDHCI_QUIRK_BROKEN_TIMEOUT_VAL |
683 		  SDHCI_QUIRK_DATA_TIMEOUT_USES_SDCLK |
684 		  SDHCI_QUIRK_SINGLE_POWER_WRITE |
685 		  SDHCI_QUIRK_NO_HISPD_BIT |
686 		  SDHCI_QUIRK_BROKEN_ADMA_ZEROLEN_DESC |
687 		  SDHCI_QUIRK_CAP_CLOCK_BASE_BROKEN,
688 	.quirks2 = SDHCI_QUIRK2_PRESET_VALUE_BROKEN |
689 		   SDHCI_QUIRK2_BROKEN_HS200 |
690 		   /*
691 		    * Auto-CMD23 leads to "Got command interrupt 0x00010000 even
692 		    * though no command operation was in progress."
693 		    *
694 		    * The exact reason is unknown, as the same hardware seems
695 		    * to support Auto CMD23 on a downstream 3.1 kernel.
696 		    */
697 		   SDHCI_QUIRK2_ACMD23_BROKEN,
698 	.ops  = &tegra_sdhci_ops,
699 };
700 
701 static const struct sdhci_tegra_soc_data soc_data_tegra30 = {
702 	.pdata = &sdhci_tegra30_pdata,
703 	.nvquirks = NVQUIRK_ENABLE_SDHCI_SPEC_300 |
704 		    NVQUIRK_ENABLE_SDR50 |
705 		    NVQUIRK_ENABLE_SDR104 |
706 		    NVQUIRK_HAS_PADCALIB,
707 };
708 
709 static const struct sdhci_ops tegra114_sdhci_ops = {
710 	.get_ro     = tegra_sdhci_get_ro,
711 	.read_w     = tegra_sdhci_readw,
712 	.write_w    = tegra_sdhci_writew,
713 	.write_l    = tegra_sdhci_writel,
714 	.set_clock  = tegra_sdhci_set_clock,
715 	.set_bus_width = sdhci_set_bus_width,
716 	.reset      = tegra_sdhci_reset,
717 	.platform_execute_tuning = tegra_sdhci_execute_tuning,
718 	.set_uhs_signaling = tegra_sdhci_set_uhs_signaling,
719 	.voltage_switch = tegra_sdhci_voltage_switch,
720 	.get_max_clock = tegra_sdhci_get_max_clock,
721 };
722 
723 static const struct sdhci_pltfm_data sdhci_tegra114_pdata = {
724 	.quirks = SDHCI_QUIRK_BROKEN_TIMEOUT_VAL |
725 		  SDHCI_QUIRK_DATA_TIMEOUT_USES_SDCLK |
726 		  SDHCI_QUIRK_SINGLE_POWER_WRITE |
727 		  SDHCI_QUIRK_NO_HISPD_BIT |
728 		  SDHCI_QUIRK_BROKEN_ADMA_ZEROLEN_DESC |
729 		  SDHCI_QUIRK_CAP_CLOCK_BASE_BROKEN,
730 	.quirks2 = SDHCI_QUIRK2_PRESET_VALUE_BROKEN,
731 	.ops  = &tegra114_sdhci_ops,
732 };
733 
734 static const struct sdhci_tegra_soc_data soc_data_tegra114 = {
735 	.pdata = &sdhci_tegra114_pdata,
736 };
737 
738 static const struct sdhci_pltfm_data sdhci_tegra124_pdata = {
739 	.quirks = SDHCI_QUIRK_BROKEN_TIMEOUT_VAL |
740 		  SDHCI_QUIRK_DATA_TIMEOUT_USES_SDCLK |
741 		  SDHCI_QUIRK_SINGLE_POWER_WRITE |
742 		  SDHCI_QUIRK_NO_HISPD_BIT |
743 		  SDHCI_QUIRK_BROKEN_ADMA_ZEROLEN_DESC |
744 		  SDHCI_QUIRK_CAP_CLOCK_BASE_BROKEN,
745 	.quirks2 = SDHCI_QUIRK2_PRESET_VALUE_BROKEN |
746 		   /*
747 		    * The TRM states that the SD/MMC controller found on
748 		    * Tegra124 can address 34 bits (the maximum supported by
749 		    * the Tegra memory controller), but tests show that DMA
750 		    * to or from above 4 GiB doesn't work. This is possibly
751 		    * caused by missing programming, though it's not obvious
752 		    * what sequence is required. Mark 64-bit DMA broken for
753 		    * now to fix this for existing users (e.g. Nyan boards).
754 		    */
755 		   SDHCI_QUIRK2_BROKEN_64_BIT_DMA,
756 	.ops  = &tegra114_sdhci_ops,
757 };
758 
759 static const struct sdhci_tegra_soc_data soc_data_tegra124 = {
760 	.pdata = &sdhci_tegra124_pdata,
761 };
762 
763 static const struct sdhci_pltfm_data sdhci_tegra210_pdata = {
764 	.quirks = SDHCI_QUIRK_BROKEN_TIMEOUT_VAL |
765 		  SDHCI_QUIRK_DATA_TIMEOUT_USES_SDCLK |
766 		  SDHCI_QUIRK_SINGLE_POWER_WRITE |
767 		  SDHCI_QUIRK_NO_HISPD_BIT |
768 		  SDHCI_QUIRK_BROKEN_ADMA_ZEROLEN_DESC |
769 		  SDHCI_QUIRK_CAP_CLOCK_BASE_BROKEN,
770 	.quirks2 = SDHCI_QUIRK2_PRESET_VALUE_BROKEN,
771 	.ops  = &tegra114_sdhci_ops,
772 };
773 
774 static const struct sdhci_tegra_soc_data soc_data_tegra210 = {
775 	.pdata = &sdhci_tegra210_pdata,
776 	.nvquirks = NVQUIRK_NEEDS_PAD_CONTROL |
777 		    NVQUIRK_HAS_PADCALIB,
778 };
779 
780 static const struct sdhci_pltfm_data sdhci_tegra186_pdata = {
781 	.quirks = SDHCI_QUIRK_BROKEN_TIMEOUT_VAL |
782 		  SDHCI_QUIRK_DATA_TIMEOUT_USES_SDCLK |
783 		  SDHCI_QUIRK_SINGLE_POWER_WRITE |
784 		  SDHCI_QUIRK_NO_HISPD_BIT |
785 		  SDHCI_QUIRK_BROKEN_ADMA_ZEROLEN_DESC |
786 		  SDHCI_QUIRK_CAP_CLOCK_BASE_BROKEN,
787 	.quirks2 = SDHCI_QUIRK2_PRESET_VALUE_BROKEN |
788 		   /* SDHCI controllers on Tegra186 support 40-bit addressing.
789 		    * IOVA addresses are 48-bit wide on Tegra186.
790 		    * With 64-bit dma mask used for SDHCI, accesses can
791 		    * be broken. Disable 64-bit dma, which would fall back
792 		    * to 32-bit dma mask. Ideally 40-bit dma mask would work,
793 		    * But it is not supported as of now.
794 		    */
795 		   SDHCI_QUIRK2_BROKEN_64_BIT_DMA,
796 	.ops  = &tegra114_sdhci_ops,
797 };
798 
799 static const struct sdhci_tegra_soc_data soc_data_tegra186 = {
800 	.pdata = &sdhci_tegra186_pdata,
801 	.nvquirks = NVQUIRK_NEEDS_PAD_CONTROL |
802 		    NVQUIRK_HAS_PADCALIB,
803 };
804 
805 static const struct of_device_id sdhci_tegra_dt_match[] = {
806 	{ .compatible = "nvidia,tegra186-sdhci", .data = &soc_data_tegra186 },
807 	{ .compatible = "nvidia,tegra210-sdhci", .data = &soc_data_tegra210 },
808 	{ .compatible = "nvidia,tegra124-sdhci", .data = &soc_data_tegra124 },
809 	{ .compatible = "nvidia,tegra114-sdhci", .data = &soc_data_tegra114 },
810 	{ .compatible = "nvidia,tegra30-sdhci", .data = &soc_data_tegra30 },
811 	{ .compatible = "nvidia,tegra20-sdhci", .data = &soc_data_tegra20 },
812 	{}
813 };
814 MODULE_DEVICE_TABLE(of, sdhci_tegra_dt_match);
815 
816 static int sdhci_tegra_probe(struct platform_device *pdev)
817 {
818 	const struct of_device_id *match;
819 	const struct sdhci_tegra_soc_data *soc_data;
820 	struct sdhci_host *host;
821 	struct sdhci_pltfm_host *pltfm_host;
822 	struct sdhci_tegra *tegra_host;
823 	struct clk *clk;
824 	int rc;
825 
826 	match = of_match_device(sdhci_tegra_dt_match, &pdev->dev);
827 	if (!match)
828 		return -EINVAL;
829 	soc_data = match->data;
830 
831 	host = sdhci_pltfm_init(pdev, soc_data->pdata, sizeof(*tegra_host));
832 	if (IS_ERR(host))
833 		return PTR_ERR(host);
834 	pltfm_host = sdhci_priv(host);
835 
836 	tegra_host = sdhci_pltfm_priv(pltfm_host);
837 	tegra_host->ddr_signaling = false;
838 	tegra_host->pad_calib_required = false;
839 	tegra_host->pad_control_available = false;
840 	tegra_host->soc_data = soc_data;
841 
842 	if (soc_data->nvquirks & NVQUIRK_NEEDS_PAD_CONTROL) {
843 		rc = tegra_sdhci_init_pinctrl_info(&pdev->dev, tegra_host);
844 		if (rc == 0)
845 			host->mmc_host_ops.start_signal_voltage_switch =
846 				sdhci_tegra_start_signal_voltage_switch;
847 	}
848 
849 	rc = mmc_of_parse(host->mmc);
850 	if (rc)
851 		goto err_parse_dt;
852 
853 	if (tegra_host->soc_data->nvquirks & NVQUIRK_ENABLE_DDR50)
854 		host->mmc->caps |= MMC_CAP_1_8V_DDR;
855 
856 	tegra_sdhci_parse_pad_autocal_dt(host);
857 
858 	tegra_host->power_gpio = devm_gpiod_get_optional(&pdev->dev, "power",
859 							 GPIOD_OUT_HIGH);
860 	if (IS_ERR(tegra_host->power_gpio)) {
861 		rc = PTR_ERR(tegra_host->power_gpio);
862 		goto err_power_req;
863 	}
864 
865 	clk = devm_clk_get(mmc_dev(host->mmc), NULL);
866 	if (IS_ERR(clk)) {
867 		dev_err(mmc_dev(host->mmc), "clk err\n");
868 		rc = PTR_ERR(clk);
869 		goto err_clk_get;
870 	}
871 	clk_prepare_enable(clk);
872 	pltfm_host->clk = clk;
873 
874 	tegra_host->rst = devm_reset_control_get_exclusive(&pdev->dev,
875 							   "sdhci");
876 	if (IS_ERR(tegra_host->rst)) {
877 		rc = PTR_ERR(tegra_host->rst);
878 		dev_err(&pdev->dev, "failed to get reset control: %d\n", rc);
879 		goto err_rst_get;
880 	}
881 
882 	rc = reset_control_assert(tegra_host->rst);
883 	if (rc)
884 		goto err_rst_get;
885 
886 	usleep_range(2000, 4000);
887 
888 	rc = reset_control_deassert(tegra_host->rst);
889 	if (rc)
890 		goto err_rst_get;
891 
892 	usleep_range(2000, 4000);
893 
894 	rc = sdhci_add_host(host);
895 	if (rc)
896 		goto err_add_host;
897 
898 	return 0;
899 
900 err_add_host:
901 	reset_control_assert(tegra_host->rst);
902 err_rst_get:
903 	clk_disable_unprepare(pltfm_host->clk);
904 err_clk_get:
905 err_power_req:
906 err_parse_dt:
907 	sdhci_pltfm_free(pdev);
908 	return rc;
909 }
910 
911 static int sdhci_tegra_remove(struct platform_device *pdev)
912 {
913 	struct sdhci_host *host = platform_get_drvdata(pdev);
914 	struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
915 	struct sdhci_tegra *tegra_host = sdhci_pltfm_priv(pltfm_host);
916 
917 	sdhci_remove_host(host, 0);
918 
919 	reset_control_assert(tegra_host->rst);
920 	usleep_range(2000, 4000);
921 	clk_disable_unprepare(pltfm_host->clk);
922 
923 	sdhci_pltfm_free(pdev);
924 
925 	return 0;
926 }
927 
928 static struct platform_driver sdhci_tegra_driver = {
929 	.driver		= {
930 		.name	= "sdhci-tegra",
931 		.of_match_table = sdhci_tegra_dt_match,
932 		.pm	= &sdhci_pltfm_pmops,
933 	},
934 	.probe		= sdhci_tegra_probe,
935 	.remove		= sdhci_tegra_remove,
936 };
937 
938 module_platform_driver(sdhci_tegra_driver);
939 
940 MODULE_DESCRIPTION("SDHCI driver for Tegra");
941 MODULE_AUTHOR("Google, Inc.");
942 MODULE_LICENSE("GPL v2");
943